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GCN Circular 2037

Subject
GRB 030324: Optical and NIR Observations
Date
2003-03-31T02:08:48Z (22 years ago)
From
Daniel E. Reichart at U.North Carolina <reichart@physics.unc.edu>
J. Moran, A. Henden, D. Lamb, D. York, M. Nysewander, J. Barentine, J.
Dembicky, C. Graziani, E. Sheldon, R. Soule, M. Bayliss, H. Cheng, C. Cook,
M. Lopez-Morales, D. Reichart, R. McMillan, B. Ketzeback, C. Blacker, and
A. Reese report on behalf of the USNO, ARC, and UNC GRB teams of the FUN
GRB collaboration:

We observed the 14 arcminute diameter error circle of GRB 030324 (Donaghy
et al., GCN 1954Loading...
 
 , 1955Loading...
 
 ) in BVRci*IcH beginning 2.1 hours after the burst.
Using the field calibration of Henden (GCN 1860Loading...
 
 ) and 2MASS, we report the
following limiting magnitudes:

Start      Start Time Mean Time Filter Integration Limiting  Telescope
Date       Since GRB  Since GRB        Time (sec)  Magnitude
           (hours)    (hours)          x Pointings (3 sigma)
Mar 24.222 2.12       2.12      Ic     300 x 1     20.2      1.0-m USNO
Mar 24.227 2.24       2.24      Rc     300 x 1     21.1      1.0-m USNO
Mar 24.232 2.36       2.96      B      3000 x 1    23.0      1.0-m USNO
Mar 24.240 2.55       3.15      V      1200 x 1    22.4      1.0-m USNO
Mar 24.259 3.00       3.30      H      600 x 4     19.0      1.55-m USNO
Mar 24.332 4.76       5.90      Rc     1478 x 4    19.2      0.6-m MO(1)
Mar 24.345 5.06       5.06      B      600 x 1     22.0      1.0-m USNO
Mar 24.349 5.16       6.22      i*     1200 x 4    23.8 -    3.5-m ARC
                                       + 2400 x 1  24.3(2)
Mar 24.353 5.26       6.49      V      2400 x 1    22.7      1.0-m USNO
Mar 24.358 5.37       6.64      Rc     2400 x 1    22.3      1.0-m USNO
Mar 24.362 5.48       6.60      Ic     2400 x 1    21.6      1.0-m USNO
Mar 24.364 5.52       5.94      H      900 x 4     19.3      1.55-m USNO
Mar 24.389 6.11       6.71      Ic     4200 x 1    16.7(3)   0.2-m PST(4)
Mar 26.477 56.22      56.74     Ic     3600 x 1    21.9(5)   1.0-m USNO

(1) Morehead Observatory telescope
(2) Mosaic pattern results in a limiting magnitude that is 23.8 on the
    sides and 24.3 in the center
(3) 5-sigma limiting magnitude
(4) Pisgah Survey Telescope at the Pisgah Astronomical Research Institute
    (PARI)
(5) Central 11.3' x 11.3'

Using the image subtraction routine ISIS2 (Alard 2000), we find no
transient sources between any of our same-filter images to limiting
magnitudes of B = 22.0, V = 22.4, Rc = 21.1, Ic = 20.2, and H = 19.0
between 2.1 and 3.3 hours after the burst.  Furthermore, we find no
transient sources between our ARC images and SDSS images of this field
taken in March 1999 to a limiting magnitude of i* = 22.2 at 6.2 hours after
the burst.

To these limiting magnitudes, GRB 030324 appears to be a dark burst, not
only at optical wavelengths, but interestingly also at NIR wavelengths.

Alard, C. 2000, A&AS, 114, 363